Taken from IMDB: Mala is a Polynesian spy in the employ of U.S. Intelligence investigates sabotage on Clipper Island. A gang of spies causes the eruption of a volcano, for which our hero is blamed. He convinces the local Princess Melani of his innocence and helps her ward off a takeover by rival high priest Porotu.
SURROUNDED BY DEVIL-SHARKS...HEMMED IN BY A BAND OF KILLERS ON AN ISLAND OF FEAR...WHO DARES DEFY THE GODS OF THE JUNGLE TO WIPE OUT THE NEW RADIO MENACE! (original ad - all caps)
14 WEEKS OF THROBBING THRILLS! WITH THE SERIAL THAT NEVER LETS YOU DOWN! (original ad - all caps)